The subject inventive concept relates to charge pumps capable of generating a boosted output voltage using a metal-oxide-semiconductor (MOS) capacitor. More particularly, the inventive concept relates to a charge pump capable of preemptively charging a parasitic capacitor within a charge pump to prevent an output voltage and/or output current from being reduced due to the parasitic capacitor. Such charge pumps will find application in various types of semiconductor devices.
It is often the case in conventional semiconductor devices that when a charge pump is configured “on chip” using a MOS capacitor, a charge-sharing phenomenon occurs between a junction capacitor and parasitic capacitors that exist between a body of a capacitor of a next node connected to a pumping capacitor and a substrate. This phenomenon tends to undesirably reduce the level of the output voltage and/or current (hereafter “output voltage/current”) provided by the charge pump.
Therefore, when a charge pump is configured on chip using a MOS capacitor, some means should be provided to compensate for this reduction of output voltage/current caused by a parasitic capacitor.